3-(2,6-Dichloro-3,5-dimethoxy-phenyl)-1-{6-[4-(4-ethyl-piperazin-1-yl)-phenylamino]-pyrimidin-4-yl}-1-methyl-urea (described in U.S. Ser. No. 11/570,983, filed Jun. 23, 2005, and incorporated by reference in its entirety herein) has the structure of Formula I:
The compound of Formula I is a protein kinase inhibitor and is useful in the treatment of proliferative diseases mediated by protein kinases. In particular, the compound of Formula I inhibits FGFR1, FGFR2, FGFR3, FGFR4, KDR, HER1, HER2, Bcr-Abl, Tie2, and Ret kinases. It is therefore useful in the treatment of cancers including AML, melanocytic neoplasia, breast cancer, colon cancer, lung cancer (especially small-cell lung cancer), cancer of the prostate or Kaposi's sarcoma.
It is well known that the crystalline form of the active pharmaceutical ingredient (API) of a particular drug is often an important determinant of the drug's ease of preparation, hygroscopicity, stability, solubility, storage stability, ease of formulation, rate of dissolution in gastrointestinal fluids and in vivo bioavailability. Crystalline forms occur where the same composition of matter crystallizes in a different lattice arrangement resulting in different thermodynamic properties and stabilities specific to the particular crystalline form. Crystalline forms may also include different hydrates or solvates of the same compound. In deciding which form is preferable, the numerous properties of the forms are compared and the preferred form chosen based on the many physical property variables. It is entirely possible that one form can be preferable in some circumstances where certain aspects such as ease of preparation, stability, etc. are deemed to be critical. In other situations, a different form may be preferred for greater dissolution rate and/or superior bioavailability. It is not yet possible to predict whether a particular compound or salt of a compound will form polymorphs, whether any such polymorphs will be suitable for commercial use in a therapeutic composition, or which polymorphs will display such desirable properties.